Eastern Pacific Black Ghostshark, Hydrolagus melanophasma
The Eastern Pacific Black Ghostshark, Hydrolagus melanophasma, whose common Spanish name is quimera negra is a species in the family the Shortnose Chimaeridae or Chimaera Family, known collectively as quimeras in Mexico. This fish is also known as the Black Ratfish. The species is very newly discovered with only a handful of fish being collected and introduced to science in 2009. Globally, there are forty-eight members of the family placed in three genera, and only five species in the genus Hydrolagus, four of which are found in Mexican waters, all in the Pacific.
The Eastern Pacific Black Ghostsharks have compressed rounded elongated bodies that taper into a filamentous tail, which is almost one-half the length of the fish. They are uniformly black with a lighter band across their snout. Their head is very large and “rabbit-like” with a short rounded broad duckbill-shaped snout, large eyes, and large nostrils. Their mouth is on the underside with two pairs of plates on the top jaw and one pair on the bottom jaw. They do not have an anal fin. Their caudal fin is elongated with two equal sized lobes and a whip-like rear filament. They have two dorsal fins, the first being large and triangular in shape with the front edge having a prominent venomous spine that is slightly taller than the fin itself, and the second having a long base with a low undulating profile of uniform height. Their well developed pectoral fins are broad and triangle-shaped and reach past the pelvic fin origin. Their pelvic fins are also broad and triangle-shaped. They have prominent lateral line canals on scaleless skin. Males have a spiny and club-shaped process located on their head (pictured below).
The Eastern Pacific Black Ghostsharks are found over and within muddy and rocky bottom habitats at depths between 100 and 5,640 feet. They reach a maximum length of 1.2 meters (3 feet 11 inches). They are feeble swimmers and locate prey primarily through electroreception and smell consuming clams, crabs, shrimps, polychaete worms, and small benthic fish. In turn they are preyed upon by larger sharks. Reproduction is oviparous with females releasing spoon-shaped egg cases every ten to fourteen days over a period of several months. They are an exceedingly rare, poorly studied species and very little is known about their behavioral patterns.
In Mexican waters the Eastern Pacific Black Ghostshark has a limited range in being found only along the west coast of Baja.
The Eastern Pacific Black Ghostshark can be confused with the smaller cold water Spotted Ratfish, Hydrolagus colliei (maximum length of 100 cm; covered with white spots).
The Eastern Pacific Black Ghostsharks are exceedingly rare, of limited value to humans, but of great interest to the scientific community.
Eastern Pacific Black Ghostshark, Hydrolagus melanophasma, male. Fish collected alive off the surface with a bait net by Pesces Sportfishing 12 miles south of Cabo San Lucas, Baja California Sur, May 2009. Length: 90 cm (35 inches). A female was also collected by the same fleet in the same location, April 2010.